As used herein, the term "vehicle" refers to land vehicles, to marine vehicles or vessels, and to aircraft. In the United States, about 1.7 million automotive vehicles and about 100,000 marine and aircraft vehicles are reported missing (or stolen) each year. The probability that a land or marine vehicle will be recovered drops dramatically after the vehicle or vessel has been missing for 24 hours or more. Thus, time is of the essence in locating and retrieving a missing vehicle.
Vehicle location and/or tracking systems are disclosed by Shelfer et al in U.S. Pat. Nos. 4,891,650 and 5,218,367, by Darnell et al in U.S. Pat. No. 5,043,736, by Durboraw in U.S. Pat. No. 5,119,341, by Wortham in U.S. Pat. Nos. 5,155,689 and 5,398,190, by Robinson et al in U.S. Pat. No. 5,159,344, by Bertiger et al in U.S. Pat. No. 5,187,805, by Song in U.S. Pat. No. 5,208,756, by Mansell in U.S. Pat. No. 5,223,844, by Dennison in U.S. Pat. No. 5,235,633, and by Simms et al in U.S. Pat. No. 5,334,974.
What is needed is a system including cellular telecommunication means that allows determination and reporting of the present location of a missing vehicle, using clandestine means on the vehicle itself and one or more cellular phone channels. Preferably, the clandestine means permits normal operation of the cellphone, regardless of who is using the vehicle or phone, but can be used to determine and transmit a report on the present location of the missing vehicle, if commanded to do so by a special message sent via the cellular network. Preferably, the system will optionally allow simultaneous use of the cellular phone system to report vehicle location and to carry a normal cellular phone conversation. Preferably, the system should allow recording of any telecommunications made using the cellular phone while the vehicle is missing.